Mist generator for sterilizing forced air systems

ABSTRACT

A mist generator improves the sterility of blowers having controlled forced air systems. In one embodiment, the mist generator has a chamber adapted to receive a disinfectant adapted for attachment to an output opening of a blower for delivery into the chamber of forced air carrying misted disinfectant. The main body also includes an output duct or aperture adapted for attachment to a second hose which, in turn, is adapted for attachment to an inlet opening of the blower for delivery of disinfectant misted air through internal components of the blower. Alternatively, there is used a disinfectant filter formed as a sterilizing grid having a screen coated with a soft porous surface material impregnated with a liquid disinfectant. The soft porous surface material releases said liquid disinfectant when forced air moves through the filter. In both embodiments, sterile water is introduced to take up residual disinfectant and the vapor captured in a dry filter or desiccant material and removed from the system. The mist generator improves the sterility of the blower to mitigate microbial contamination of forced air delivery systems.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of applicant's co-pendingU.S. patent application Ser. No. 15/722,822, filed Oct. 2, 2017 which,in turn, is a continuation-in-part of applicant's co-pending U.S. patentapplication Ser. No. 15/334,507, filed Oct. 26, 2016, now U.S. Pat. No.9,901,483 which, in turn, is a continuation-in-part of U.S. patentapplication Ser. No. 15/056,120, filed Feb. 29, 2016, now U.S. Pat. No.9,504,601, the disclosures of which are hereby incorporated in theirentirety by reference thereto.

1. FIELD OF THE INVENTION

The present invention relates to improvements in sterility of forced airsystems; and, more particularly, to an antimicrobial mist generatorutilized with systems employing forced air, heated air or cooled air,such as hospital equipment, health care equipment, commercial and/orresidential forced air systems, for facilitating and/or maintainingsterility.

2. DESCRIPTION OF THE PRIOR ART

Numerous prior art patents and disclosures relate to warming of apatient mattress or blanket by the passage of warmed fluids. Warmedfluids may be heated water or heated air. If a fluid-filled device leaksor ruptures, the heated water disadvantageously creates puddles ofleaked water around the patient and on the operating room floor. Waterfilled blankets are heavy, and the patient may find these blanketshighly uncomfortable. Mattresses and blankets that circulate warm airdischarge the air through a plurality of exit passages in the form ofhigh velocity jets. Because the internal conduits of the blower are notsterile, the air discharged from the device may contain microbes. Thedischarge also creates turbulent circulation currents in the room airthat may pick up microbes in floor dust and deliver them to thepatient's operative area, as well as hospital room workers.

U.S. Pat. No. 1,121,277 to Mitchell discloses a warming appliance forbeds. This warming apparatus circulates warm water. The disclosure ofthis patent shows the bed having a plurality of pipes through whichheated water is circulated. A hot water heater or boiler is connected toa pipe that feeds the bed heating pipes. Warm air is not circulatedthrough the bed.

U.S. Pat. No. 2,259,712 to Sweetland discloses a bed warmer apparatus. Afan blows air through an electric heater and the warmed air is passedthrough a pipe in the bed. The bed warmer requires power to drive theblower motor. A flexible hose conveys warm air to the cushion, whichserves the double purpose of supporting the bed cover and providingwarmth in the bed. A conventional type of bed cover is used. The blowerpasses air over electrical heaters to warm the air, which is passedthrough pipes in the bed. The interior of the blower is not sterilized.The warm air is not returned to the blower since this is not a closedsystem. Release of the warm air can cause currents of unsterile air,containing bacteria, to surround the patient or the operative site,increasing prospects for infections.

U.S. Pat. No. 2,504,308 to Donkle discloses a heating and cooling cover.The bed has a heating or cooling cover supplied with working fluid froma refrigerator or a heat pump. The cover does not employ warm air. Aworking fluid is returned to the refrigeration or heat pump systemthrough a heat exchanger, which heats or cools the area adjacent to therefrigeration or heat pump unit.

U.S. Pat. No. 2,753,435 to Jepson discloses a thermal blanket. Thethermal blanket is on a bed and is provided with a fluid circulatingunit. The fluid circulating unit is provided with a knob to adjust thetemperature of the thermal blanket. The fluid is indicated to bedistilled water. The device disclosed by the Jepson patent does notcirculate warm air within the blanket.

U.S. Pat. No. 2,978,225 to Dallas discloses a thermal blanket. Thethermal blanket is provided with tubes through which liquid iscirculated. The thermal blanket has a plurality of fluid passagewaysdisposed in a parallel relationship. The edge includes a liquiddistribution manifold unit. The thermal blanket does not circulate warmair to provide warmth to the patient.

U.S. Pat. No. 4,094,357 to Sgroi discloses a heat transfer blanket. Theheat transfer blanket has a plurality of flexible sheath heat pipes thatprovide a uniform heating or cooling pattern therein. The ends of theflexible heat pipes that are free from the blanket are thermally coupledto a combination heating and cooling system. When utilizing the heatingsystem, the flexible heat pipes provide elevated temperatures at theblanket surfaces. When utilizing the cooling system, the flexible heatpipes provide lower than ambient temperatures at the blanket surfaces. Asolid metallic rod is affixed to one end of the pipe. A wick extends theentire length of the interior of the pipe, which is partially filledwith a liquid that becomes a vapor upon sufficient heating. The end ofthe pipe in which liquid is situated accepts heat from the surroundingarea, causing the liquid to vaporize. The vapor ultimately communicateswith the other end of the pipe. At this end, cooling effects areintroduced, and the vapor condenses back to a liquid state. Liquid thentravels along the wick to the end of a tube containing the liquid. Theefficiency of thermal coupling between opposite ends of the heat pipe issubstantially higher than the coupling efficiency of an equivalentdiameter and length of a solid copper rod. The heat transfer means forwarming or cooling the blanket is by evaporation heating or cooling ofliquid contained in the wick. Warm air is not passed within pipes in theheat transfer blanket.

U.S. Pat. No. 4,132,262 to Wibell discloses a heating and coolingblanket. This cooling and heating blanket has a blanket enclosure withheating means including a plurality of flexible elements positionedwithin the enclosure for being electrically energized to supply heat tothe enclosure so that the enclosure may be retained above roomtemperature. A cooling means includes a plurality of flexible fluidcarrying conduits positioned within the enclosure through which a heattransfer fluid can flow, such that the enclosure may be retained belowroom temperature. Control means including an electric motor and a pumpdriven thereby are located remotely relative to the enclosure. Aflexible conduit means connects the enclosure and the cooling means. Aregulating means is operatively associated with the heating means andthe cooling means. The regulating means is adapted to energize thecontrol means or the heating means in response to increases anddecreases of the temperature associated with the enclosure. With thisarrangement, the temperature of the blanket may be retained above orbelow the room temperature in which the blanket is located. The heatingand cooling means are separate from each other. The heating meanscomprises electrical heating wires, which are heated by the passage ofan electrical current. Heating of the blanket is not achieved by thepassage of warm air.

U.S. Pat. No. 4,777,802 to Feher discloses a blanket assembly andselectively adjustable apparatus for providing heated or cooled airthereto. This blanket assembly has an outer layer constructed of arelatively close-weave fabric preventing airflow therethrough.Underneath the top layer is a second layer of material edge connected tothe top layer and which is constructed of a material permeable to air,such as relatively thin taffeta, for example. A cavity between the twolayers receives pressurized cooled or heated air that passes through theair-permeable layer to cool or heat the individual using the blanketassembly. A modified blanket assembly construction includes rigid edgewall members holding the outer and inner layers separated at apredetermined spacing. This reduces “pinch-off” between the layers thatwould restrict airflow within parts of the cavity or chamber. Peltiereffect elements are selectively energizable to heat or cool air providedto the blanket assembly cavity. The heating/cooling of the patient bedis effected by a closed circuit with a solid-state PN junction to createthe heating/cooling based on the Peltier effect. Passage of directcurrent in one direction causes one PN junction to heat while the otherjunction cools. The heated PN junction supplies heat to warm the patientbed while the coolness of the other junction is discharged in airsurrounding the patient as well as the operating room. The devicedisclosed by the Feher patent does not use circulation of warm air in aclosed system to warm the bed of a patient, and there is nosterilization of the internal portion of the system, creating thepossibility of infecting the patient and workers in the operating room.

U.S. Pat. No. 4,884,304 to Elkins discloses a bedding system withselective heating and cooling. This bedding system has provision forheating or cooling a person and for applying the heating or cooling onlyin areas of the bed where the person is located. A sealed three-ply heattransfer and insulating device covers the mattress, below the contoursheet or other covering which comes in contact with the person's body. Awicking contour sheet or other cover capable of absorbing anycondensation on the surface of the three-ply device may optionally beused. Between the lower two plies of the three-ply material is channeleda flow of coolant liquid at a regulated temperature that is close tohuman skin temperature. Above these two plies. i.e., between the middleply and the upper ply, is a sealed envelope containing slightlypressurized air. A lightweight, well-insulated comforter is alsorecommended to isolate the sleeper from the thermal ambient environment.The bedding system includes a temperature control unit and a mattresscover device, which is positioned over a mattress. The mattress coverdevice includes liquid flow channels and preferably a gas envelope orplenum space located above the liquid flow channels. The multiplicity ofliquid flow channels is interconnected to form one or more circulationpaths. The mattress is heated by liquid flow channels. It is not heatedby the passage of warm air.

U.S. Pat. No. 5,968,084 to Augustine et al. discloses a thermal blanket.This thermal blanket includes an inflatable covering with a head end, afoot end, two edges and an undersurface. The covering is inflatedthrough an inlet at the foot end by a thermally controlled inflatingmedium. An aperture array on the undersurface of the covering exhauststhe thermally controlled inflating medium from the covering. Exhaustport openings are provided at the edges of the covering to vent theinflating medium, which enhances circulation of the thermally controlledmedium through the cover. An uninflatable section is provided at thehead end, together with an absorbent bib attached to the covering,adjacent the uninflatable section. An uninflatable section may also beprovided at the foot end, having a pair of seams to form an erectabledrape section. When inflated, the device self-erects and provides a bathof thermally controlled inflating medium to the interior of the erectedstructure. The enhanced circulation of the medium through the coversmaintains a relatively high average temperature under the blanket and arelatively uniform distribution of temperature in the inflating medium,which is exhausted through the apertures into the structure's interior.When the structure covers a patient, the uninflatable section at thehead end provides a relatively unobstructed view of the patient's face,while the absorbent bib maintains a relatively sanitary environment inthe area beneath the patient's head. The uninflatable section at thefoot end retains heat from the inflating medium to warm the patient'sfeet and insulate the bare skin of the feet from excessive conductiveheat from the hose connected to the inflation inlet. The thermal blanketmay be sized to cover selected areas of a patient, such as the upperbody, including the chest, arms, or shoulders, or the lower body,including the pelvic and groin area and the legs. The warmed air isexhausted underside of the thermal blanket through the aperturesprovided. The flow of warm air through the apertures occurs at highvelocity, thus bringing microbes and dust to the patient by theturbulent movement of ambient airflow.

U.S. Pat. No. 7,114,204 to Patrick discloses a method and apparatus fortransferring patients. This patient transfer apparatus includes aninflatable mattress, alternatively with a rigid top board with a patientrestraint system on which a patient can be placed, when patientimmobilization is required. A portable cart is included with a chamberfor storage of a plurality of mattresses.

U.S. Pat. No. 7,837,721 to Augustine, et al. discloses a patient comfortapparatus and system. This apparatus and system thermally comfort apatient; and includes a clinical garment such as a hospital gown, robe,bib, and other equivalents provided with pneumatic, convective thermaltreatment for persons or animals. The pneumatic convective deviceprovides convective warming focused or directed primarily on the thoraxor body core. The pneumatic convective device includes at least oneinlet accessed through a clinical garment, a region in distribution withthe inlet for distributing a stream of pressurized, thermally treatedair, and a permeable member for emitting pressurized, thermally treatedair from the distribution region. As shown in FIG. 1A, the sheets 114and 116 form between themselves a pneumatic structure to receive anddistribute pressurized air within itself. At least one permeable memberof the device (the sheet 114, for example) cooperates with the pneumaticstructure to emit pressurized air from the device. In this regard, oneend of an air hose may be received through an inlet port 127. A streamof pressurized, thermally conditioned air introduced through the airhose fills the space between the sheets 114 and 116 and is distributedthroughout the space. The pressurized air is emitted from the pneumaticstructure through the air-permeable sheet 114. Motion of the emitted airsupports heat transfer with a body adjacent, next to or near thepneumatic structure facing the permeable sheet 114. The permeable sheethas holes that deliver the pressurized warm air at high velocity,producing turbulent airflow adjacent to the patient, bringing dust andmicrobes to the patient

U.S. Pat. No. 8,414,671 to Augustine, et al. discloses personal airfiltration devices for use with bedding structures. These devices,methods, and systems create a zone of filtered air proximate a patient'shead. They include an air filtration device having a blower configuredto be disposed within, below, or affixed to a bedding structure; an airplenum in flow communication with the blower and in support of the headof the user and having an air delivery surface configured to distributethe air flow to the zone of filtered air; and a filter disposed withinthe device for filtering the air flow before it is distributed to thezone of filtered air. Filtered air is exhausted, surrounding thepatient, and producing airflow that is turbulent and can delivermicrobes and dust to the patient. There is no sterilization of theinterior of the blower, as recommended by the FDA.

U.S. Pat. No. 5,225,167 to Wetzel discloses a room air sterilizer mountson the wall of the room and traps airborne particulate in a HEPA filter.An ultraviolet germicidal lamp destroys any biocontamination on thetrapped particulates. The sterilizer has an elongated vertical housingwith a return air grille near or at its lower end and a HEPA filterassembly disposed at an outflow port at its upper end. The HEPA filteris preferably a quarter cylinder, and the sterilizer lamp is situated toexpose the inner or intake side of the filter to the sterilizingultraviolet radiation. A prefilter can be situated ahead of the blowersfor the sterilizer and can have an associated ultraviolet sterilizerlamp.

U.S. Pat. No. 5,015,442 to Hirai discloses a sterilizing/deodorizingapparatus having a fan for creating airflow in one direction in abox-like body. The body has divided air passages, one of the airpassages having an ozonizer and an air-permeable ozone-decomposingcatalyzer, and the other air passage simply allowing untreated air toflow therethrough.

U.S. Pat. No. 5,417,729 to Greenleaf discloses a modular air cleaningsystem having at least one filter module having a closed plenum boxprovided with male and female air flow porting structure, one of whichporting structure provides an air inlet, and the other of which providesan air outlet, each of the porting structures is in substantiallycylindrical form, and projects outwardly from the box and each has asection of substantially the same diameter lying adjacent the box, ashoulder on each of the sections peripherally circumscribing the same ata short distance outwardly from the box and adapted to engage endportions of a flexible hose for preventing its withdrawal from thesections, the male porting structure having a reduced diameter segmentlying outwardly of the adjacent section and adapted to telescope withinthe female porting structure of another plenum box, and an annular sealwithin the female porting structure adapted to engage the segment andform a substantially gas-tight seal there against.

U.S. Pat. No. 5,523,057 to Mazzilli discloses a filtration system foruse in residential and commercial buildings. The filtration apparatusconsists of a galvanized steel for support of a tactified filterfollowed by a 254 nm ultraviolet light with the sterilized air thenpassed through an activated carbon filter for removal of chemicalvapors. The filtration apparatus works in conjunction with a remotelylocated power supply pack, which includes an air pressure activator toallow operation of the ultraviolet lights only when air movement isdetected in a ventilation system. Installation of the device is compact,allowing placement in residential locations in conventional heater andair conditioning systems.

U.S. Pat. No. 6,508,989 to Urrusti, et al. discloses an airsterilization system for child incubators to provide the child with airwhich is less polluted or free from pathogenic microorganisms that mightput its health at risk or prolong its stay in the incubator and/orclinic or hospital, and that of the other persons or patients that mightcome into contact with the air exiting the same incubator in the case ofa child with an infectious manifestation.

U.S. Pat. No. 8,066,947 to Niazi discloses an air scrubber foreliminating associated airborne contaminants and sterilizing airprovided to protect against nosocomial infections, environmentalallergens, weapons of biological and chemical attacks, and operationsrequiring a clean environment. The air scrubber includes a housingcontaining an alkali solution at pH 14 through which air passes andsuspended liquid particles removed; provides are made for use in centralair-conditioning systems, stand-alone applications, and portable usealong with respirators.

U.S. Pat. App. Pub. No. 20060076507 to Avnery discloses a system forsterilizing air, including an air duct for flowing the air therethrough.A first electron beam generator is positioned relative to the duct forirradiating the air flowing therethrough with a first electron beam. Thefirst electron beam disables biological substances within the air.

It has been found that sterilization of forced-air blowers utilized forwarming blankets and mattresses is necessary and has been specificallyrecommended by the FDA. Standards being implemented require frequentcleaning and sterility owing to findings that contaminated forced aircan increase the concentration of contaminated airborne particles over asurgical site. Despite the finding that forced-air blowers need regularmaintenance and cleaning, the current cleaning method typically involvessimply wiping down the blower device. Wipe-down of the blower frequentlyfails to clean the inside of the blower itself, and therefore forced-airfrom the blower typically poses contamination threats to the surgicalsite when the forced-air blower is being used with patient warmers orlifters.

Based on the foregoing, there exists a need in the art for improvedsterility of the internal components of non-closed circuit forced hotair warmers/blowers, thereby mitigating and/or preventing infections ofpatients when the blower is being utilized, as well as decreasingexposure of contaminants of operating room hospital workers andoccupants of commercial and residential buildings.

SUMMARY OF THE INVENTION

The present invention provides a system for an antimicrobial mistgenerator for use as a stand-alone internal sterilizer for closedcircuit and open circuit forced hot air devices that deliver heated airwith improved sterility. An antimicrobial mist generator is in-line witha forced-air blower to sequentially circulate antiseptic solution,water, and clean-air within the internal components of the forced airsystem, forming a closed system during the process. The antimicrobialmist generator may be employed in a closed system device or in anon-closed system device that is temporarily adapted to connect to themist generator for disinfection. The mist generator is first partiallyfilled with a liquid disinfectant, which is taken up by the forced aircirculating through the chamber and delivered into the internalcomponents of the blower to clean and sterilize the components. Once thechamber is dry, water is placed in the chamber and is taken up by thecirculating air, which becomes saturated with water vapor. The residualdisinfectant in the system is dissolved into the water vapor circulatingin the saturated air. A desiccant or other dry material is then placedin the chamber. The water vapor and dissolved residual disinfectant aretaken up in the dry material. When the cycle is complete, the chamber isdisconnected and discarded, the air lines reconnected, and air can thenbe circulated through an internally sterile system. After use of theantimicrobial chamber, this sanitation of the internal componentsprevents unsterile air currents containing microbes from being deliveredfrom the blower when it is in-line with a patient warmer, lifter orother machine, thereby decreasing the risk of infection from blowercontaminants.

The mist generator delivers an antimicrobial or disinfectant through ablower and/or blower system in order to sterilize the blower and/orblower system and decrease the possibility of exposure to infectingmicrobes. It is intended to perform internal sterilization of the blowerand/or blower system, including the blower, blower vents, internalblower components, air vents, and hoses. The present invention relatesto improvements in the sterility of forced air systems employing forcedair, heated air and/or cooled air, including, for non-limiting example,hospital machines/health care equipment, /portable oxygenmachines/commercial and/or residential forced air systems forfacilitating and/or maintaining internal sterility. Hospitalmachines/health care equipment contemplated include respirators,anesthesia machines, and the like. Commercial and/or residential forcedair systems include a full range of blower/forced air devices for usewith heaters, coolers, and air blowers, such as those used in commercialand/or residential forced air systems, as well as forced air systems,such as air conditioners and the like, used in land vehicles, includingtrucks, automobiles, trailers and tractors. These systems may includeheating or cooling systems for residential and commercial buildings(hospitals, high-rise, or otherwise involving units sharing forced airsystem components or vents), transportation vehicles (cruise ships,boats, trains, airplanes, and the like). Savings in reduced material andproduction costs, as well as weight reduction and improved sterility,represent improvements in maintaining sterilization of these blowersystems.

In a first embodiment, the mist generator for improved sterility ofblowers having controlled forced air comprises a main body having a topwall with an opening, the opening traversing into a chamber adapted toreceive a disinfectant, sidewalls and a bottom wall. An inlet duct isprovided that is adapted for attachment to a first hose which, in turn,is adapted for attachment to an output opening of the blower fordelivery of forced air into the chamber to carry misted air. An outputduct is adapted for attachment to a second hose which, in turn, isadapted for attachment to a blower inlet opening of the blower fordelivery of disinfectant misted air, water, and clean air throughinternal components of the blower. The mist generator improves thesterility of the blower to mitigate microbial contamination of forcedair delivery systems.

Another aspect of the invention provides a mist generator for improvedsterility of blowers having controlled forced air delivery, comprising adisinfectant filter formed as a sterilizing grid having a screen coatedwith a soft porous surface material impregnated with a liquiddisinfectant, wherein said disinfectant is released from the soft poroussurface into the air passing through the filter. When the filter is dry,it can be removed and impregnated with clean or sterile water. Thefilter is reinserted, and the air flowing through the system takes upthe water. This can be repeated, or another separate filter, moistenedwith water, may be used. This water again dissolves the residualdisinfectant within the system. The water, including the containeddisinfectant, is removed by inserting a dry filter and allowing thecirculating water to be taken up by the dry filter, which is removed anddiscarded. The mist generator cycle improves the sterility of the blowerto mitigate microbial contamination of forced air delivery systems.

BRIEF DESCRIPTION OF THE DRAWING

The invention will be more fully understood and further advantages willbecome apparent when reference is had to the following detaileddescription of the preferred embodiments of the invention and theaccompanying drawing, in which:

FIG. 1 illustrates an embodiment of a system for delivering warm air topatient beds and blankets in a closed circulating circuit;

FIG. 2 illustrates an embodiment of the blower with air warmer machineryand flexible tubes being sterilized by the antimicrobial mist generator;

FIG. 3 illustrates details of an embodiment of themicroprocessor-controlled blower with input port 202 and an output port,both provided with HEPA filters;

FIG. 4 illustrates an embodiment of the antimicrobial mist generator;

FIG. 5 illustrates an embodiment of the patient mattress or blanket;

FIG. 6 illustrates an embodiment of the sterilization process of thepatient bed or blanket prior to disposal;

FIG. 7 illustrates another embodiment of the microprocessor-controlledantimicrobial mist generator;

FIG. 8 illustrates the embodiment of FIG. 7 connected to a blower withair warmer machinery and flexible tubes being sterilized by theantimicrobial/disinfectant mist generator;

FIG. 9a illustrates another embodiment of the antimicrobial mistgenerator;

FIG. 9b illustrates another embodiment of a spray capsule/cartridgeadapted to be inserted within the mist generator of FIG. 9 a;

FIG. 9c illustrates an embodiment of a capsule/cartridge adapted to beinserted within the mist generator of FIG. 9 a;

FIG. 9d illustrates another embodiment of a capsule/cartridge adapted tobe inserted within the mist generator of FIG. 9 a;

FIG. 10 illustrates the embodiment of FIG. 9 connected to a blower withair warmer machinery and flexible tubes being sterilized by theantimicrobial/disinfectant mist generator;

FIG. 11 illustrates another embodiment of the antimicrobial mistgenerator;

FIG. 12a illustrates another embodiment of the antimicrobial mistgenerator adapted for temporarily creating a closed circuit to sterilizeinternal structures with disinfectant vapor of a convective temperaturemanagement system used in a hospital or surgery center;

FIG. 12b illustrates the antimicrobial mist generator temporarilyconnected to the convective temperature management system;

FIG. 13 illustrates an embodiment of the antimicrobial mist generatortemporarily attached to a hospital ventilator, anesthesia machine, oroxygen support system;

FIG. 14a illustrates another embodiment of the antimicrobial mistgenerator in which a closed circuit is temporarily created to sterilizeinternal structures with the disinfectant vapor of a heating/cooling/aircirculation device;

FIG. 14b illustrates a top plan view wherein the sterilizing grid isinserted in the system and the system is configured in a closedcirculating circuit for sterilization.

DETAILED DESCRIPTION OF THE INVENTION

The objective of the invention is to provide a mist generator fordelivering an antimicrobial or disinfectant mist to a blower and/orblower system in order to sterilize the blower and/or blower system anddecrease the possibility of exposure to infecting microbes. The subjectmist generator is intended to perform internal sterilization of theblower and/or blower system, including the blower, blower vents,internal blower components, air vents, and hoses. The present inventionrelates to improvements in the sterility of forced air systems employingforced air, heated air and/or cooled air, including, for non-limitingexample, hospital machines/health care equipment, portable oxygengenerators/commercial and/or residential forced air systems forfacilitating and/or maintaining internal sterility. Hospitalmachines/health care equipment contemplated include respirators,anesthesia machines, and the like. Commercial and/or residential forceair system uses include a full range of blower/forced air devices foruse with heaters, coolers, and air blowers, such as those used incommercial and/or residential forced air systems, as well as forced airsystems, such as air conditioners and the like, used in land vehicles,including trucks, automobiles, trailers and tractors. These systems mayinclude heating or cooling systems for residential and commercialbuildings (hospitals, high-rise, or otherwise involving units sharingforced air system components or vents), transportation vehicles (cruiseships, boats, trains, airplanes, and the like). Most have removableand/or disposable filters which help to remove dust particles from theairflow but do not sterilize or disinfect the interior of the machines.Savings in reduced material and production costs, as well as weightreduction and improved sterility represent improvements in maintainingsterilization of these blower systems.

In one aspect, the subject chamber is appointed to be used with opencircuit heating/cooling devices, including for example commercial and/orresidential forced air systems and/or aircraft, cruise ship and/or trainforced air systems, to create the temporarily closed circuit duringsanitization of these devices. Generally, in one aspect, the mistgenerator includes a chamber having an input connected via a hose to anair output of a blower of a system to be sanitized, and an outputconnected to an end of the return via a hose connected to an airintake/undersurface of the blower. Liquid disinfectant/water is placedin the chamber up to a fill line located at a level under the input andoutput of the mist generator's chamber. As hot air from the blower blowsinto the chamber, disinfecting mist is generated and is blown into theair intake of the blower to sanitize the internal components within theblower. A connection port is provided for attachment of the hose fromthe chamber to fit over and preferably substantially completely coverthe blower air input or return vent/port. The connection port preferablyincludes a rim with an adhesive located thereon for adhesive, temporaryattachment to the blower air input port/vent. If there are multiplereturn ports in the system, only one return remains open. Coverage ofany return port may also be achieved with a sheet of plastic wrap, heldover the port by its inherent adherence and the slight suction generatedby the airflow. After the mist stage is finalized and the liquidevaporated, dry desiccant and/or a hygroscopic absorbent substance isinserted into the chamber, and air continues to run so that anyremaining moisture in the closed-circuit system is absorbed by thedesiccant. After sterilization is complete, the mist generator isdisconnected from the forced air device, and the device is reconnectedto its operation configuration. The subject mist generator and itscontents may be disposable. Alternatively, the mist generator may bereusable.

Temporary conversion to a closed circuit is implemented as the subjectmist generator/antimicrobial chamber is used to sterilizeheating/cooling/air circulation device internal structures and hoseswith disinfectant vapor. In another aspect of the invention, adisinfectant filter or sponge is inserted into the main system with allbut one outlet closed. The disposable filter or sponge is shaped to fitinto a filter slot of the forced air system. When dry, the filter/spongeis removed and saturated with water or another moist sponge/filter isinserted. The system is again run and the disinfectant is taken up inthe water vapor. Finally, a dry filter/sponge is inserted, and thesystem is run “dry” to capture moisture in the filter or chamber withdesiccant therein. Lastly, all outlets of the system are opened. Theconvenience associated with insertion of the disinfectant filter orsponge and its ready replacement with a dry filter/sponge commend thisaspect of the invention for use in forced air systems, such as airconditioners and the like, used in land vehicles, including trucks,automobiles, trailers, tractors, aircraft, cruise ships and trains.

In yet another aspect of the invention, the subject mist generator fordelivering an antimicrobial or disinfectant mist is utilized forhospital equipment or health care equipment that implements a forced airunit or blower, such as for non-limiting example, intraoperative patientwarmers and/or patient lifters, respirators, anesthesia machines, forcedair chambers, isolation chambers, and the like, for internalsterilization. Usage for patient warmers, intraoperative mattresses,hospital ventilators, anesthesia machines, portable oxygen machines (02concentrators) carried by patients, and/or oxygen supply systems inorder to sterilize the blower for later use, thereby decreasing thepossibility of patients suffering infections and hospital workers in theoperating room being exposed to infecting microbes. The subject mistgenerator is intended to perform internal sterilization of the blowerand hoses of medical devices.

The generator must be used in a closed circuit, although that may beonly temporary. Disinfectant or antimicrobial is introduced into thechamber and vaporized by warm air circulated by the blower. After thedisinfectant sterilizes the inside surfaces of the blower and hoses, analiquot of water is introduced into the chamber and is similarlyvaporized, taking up the disinfectant residue. A dry desiccant is thenappointed to be introduced into the chamber and absorbs the mist. Afterthe mist is absorbed and the system is clean and dry, the blower is thenturned off. The mist generator is removed from the system and discarded,if it is disposable; or, if not disposable, is simply emptied.

The subject antimicrobial or disinfectant mist generator is operable asa stand-alone internal sterilizer for non-closed-circuit hot forced airdevices or blowers, including medical devices, commercial and/orresidential devices, and devices for transportation. Internalsterilization of the blowers is effectuated through use of theantimicrobial mist generator to mitigate virus and/or infection riskscaused by contaminated airflow of the forced air device or blower. Thesystem both disinfects the interior of the device and recaptures thedisinfectant, so that disinfectant vapor is not blown out of the machineand people are not subjected to inhaling chemical vapors.

An outflow/output duct of the antimicrobial mist generator is attachedto a flexible hose that connects to an air inflow duct of any non-closedcircuit device, temporarily making it run as a closed circuit andallowing internal sterilization, including drying, without releasingdisinfectant vapor into the environment. The antimicrobial mistgenerator is preferably, but not necessarily, disposable; and achievesthe internal sterilization that is currently impossible with patientheating devices now in use. Concerning medical equipment, the FDA hasrecommended “regular cleaning” of patient heating devices; therefore,the subject antimicrobial mist generator provides an add-on stand-aloneinternal sterilizer for ready compliance with FDA recommendations. Inone embodiment, the antimicrobial mist generator avoids a port into itschamber that could be opened for filling and instead is constructed tohave a soft diaphragm through which fluids are introduced with a needleand syringe, similar to medicine vials, in order to avoid contamination.Desiccant is then introduced into the chamber via a removable port.

The term non-closed circuit or open circuit refers generally to blowershaving an outlet air duct for delivering forced air to a blower systemimplemented in hospital equipment, commercial and/or residential forcedair systems, and/or transportation forced air systems, and an air inletduct for pulling air from the atmosphere into the blower and no returnof warm air to the blower. As used herein, the term closed-circuitrefers generally to a pathway wherein there is a closed loop with nowaste outlet or perforation of the blanket with all air returned via aseparate duct to the blower.

Concerning medical equipment, for example, measurements have shown thata surgical patient under anesthesia loses about 1.6 degrees C. bodytemperature during the first hour. Such body temperature loss can leadto hypothermia, shivering, and may compromise the patient's healingability. [Seehttp://solutions.3m.com/wps/portal/3M/en_EU/Healthcare-Europe/EU-Home/Products/InfectionPrevention/Patient_Warming/.]Patient warming beds and warming blankets are essential to prevent thisonset of patient hypothermia. For the past two decades, maintenance ofpatient body temperature during surgery has largely been achieved withforced hot air warming; this process replaced circulating hot waterblankets, which were cumbersome and often ruptured, covering the floorwith water. Tent, blanket, and mattress designs have also been used.Virtually all of these have been inexpensive and disposable, and haveattempted to avoid the problem of difficult and often incompletecleaning between uses. All of the currently used forced hot air deviceshave a blanket or pad with multiple holes that emit the warmed airaround the patient or an open tent over the patient into which the warmair is blown. Some recent studies have documented that the release orleakage of the forced air causes unwanted air currents that bring uppotentially unclean air from near the floor or cause increased numbersof particles and bacteria to circulate over the prepped area of thesurgical incision, increasing the risk of operative infection.Examination has also revealed bacteria collecting within the blowers.Another study demonstrated that air currents interfere with the laminarairflow, sometimes used in the operating room to discourage bacterialcontamination. The FDA has also recently released an alert, describingtheir concerns and the need for a regular program of cleaning andmaintenance of heater/cooler devices. While the contention that thesedevices are related to an increase in operative infections has beenquestioned, it seems reasonable to attempt to avoid air leakage and anypossibly undesirable air currents that might increase infection risk.Avoiding the buildup of bacteria within the blower is obviously areasonable goal. Bacterial contamination related to increased infectionhas recently been reported in the liquid of water blankets. Staying witha forced hot air system that employs inexpensive, disposable mattresses,and blankets that do not need to be cleaned is clearly desirable.

Recently FDC has issued the following warning located athttp://www.medscape.com/viewarticle/852750 which is reproduced below:

FDA Warns Infections a Risk With Heater-Cooler Devices

-   -   Megan Brooks    -   Disclosures|Oct. 15, 2015

The use of heater-cooler devices has been associated with nontuberculousmycobacterium (NTM) infections, primarily in patients undergoingcardiothoracic surgeries, the US Food and Drug Administration (FDA)warned today.

Heater-cooler devices are used during medical and surgical procedures towarm or cool a patient, as appropriate. The devices include water tanksthat provide temperature-controlled water to external heat exchangers orwarming/cooling blankets through closed circuits.

Although the water in the circuits does not come into direct contactwith the patient, there is the potential for contaminated water to enterother parts of the device or transmit bacteria through the air, via thedevice's exhaust vent, into the environment and to the patient, the FDAnotes in a safety communication posted on its website. Between January2010 and August 2015, the FDA received 32 reports of patient infectionsassociated with heater-cooler devices or bacterial heater-cooler devicecontamination, with 25 reported this year.

“Some reports describe NTM infections related to cardiothoracicsurgeries, but other reports do not specify the procedure the patientwas undergoing,” the FDA notes. Eight reports were related to threeevents describing patient infections occurring in US healthcarefacilities, whereas the other 24 reports involved facilities outside theUnited States, mostly in Western Europe.

In some cases, patients presented with infections several months toyears after their surgical procedure. The FDA is not aware of NTMinfections acquired by hospital staff.

The FDA says it is “actively” monitoring the situation and will provideupdates as appropriate.

The aim of today's safety communication is to “heighten awareness aboutinfections associated with heater-cooler devices and steps health careproviders and health facilities can take to mitigate risks to patients,”they say.

-   -   Recommendations

In addition to following standard precautions, the FDA recommends thathealthcare facilities and staff using heater-cooler devices considerimplementing the following measures to reduce risk to patients:

Strictly adhere to the cleaning and disinfection instructions providedin the manufacturer's device labeling. Ensure you have the most currentversion of the manufacturers' instructions for use readily available topromote adherence.

Do not use tap water to rinse, fill, refill, or top-off water tanks, asthis may introduce NTM organisms. Use only sterile water or water thathas been passed through a filter of less than or equal to 0.22 microns.When making ice needed for patient cooling during surgical procedures,use only sterile water or water that has been passed through a filter ofless than or equal to 0.22 microns. Deionized water and sterile watercreated through reverse osmosis is not recommended because it maypromote corrosion of the metal components of the system.

Direct the heater-cooler's vent exhaust away from the surgical field tomitigate the risk of aerosolizing heater-cooler tank water into thesterile field and exposing the patient.

Establish regular cleaning, disinfection, and maintenance schedules forheater-cooler devices according to the manufacturers' instructions tominimize the risk for bacterial growth and subsequent patient infection.

Develop and follow a comprehensive quality control program formaintenance, cleaning, and disinfection of heater-cooler devices. Yourprogram may include written procedures for monitoring adherence to theprogram and documenting set up, cleaning, and disinfection processesbefore and after use.

Immediately remove from service heater-cooler devices that showdiscoloration or cloudiness in the fluid lines/circuits, which mayindicate bacterial growth. Consult your hospital infection controlofficials to perform the appropriate follow-up measures and reportevents of device contamination to the manufacturer.

Consider performing environmental, air, and water sampling andmonitoring if heater-cooler contamination is suspected. Environmentalmonitoring requires specialized expertise and equipment to collect andprocess samples, which may not be feasible in all facilities.

Healthcare facilities should follow their internal procedures fornotifying and culturing patients if they suspect infection associatedwith heater-cooler devices.

Aspects of the present invention address the aforementioned issues byproviding an antimicrobial mist generator operable as a stand-aloneinternal sterilizer for closed and non-closed-circuit blowers. Internalsterilization of the blower through use of the antimicrobial mistgenerator mitigates infection risks caused by contaminated airflow ofthe patient blower when it is being used with patient lifters and/orwarmer devices. An outflow chamber/output duct of the antimicrobial mistgenerator is attached to a flexible hose that connects to an air inflowof any non-closed circuit device, temporarily making it run as a closedcircuit and allowing internal sterilization, including drying, withoutreleasing disinfectant vapor into the hospital environment. Theantimicrobial mist generator, presumably, but not necessarilydisposable, achieves the internal sterilization that is currentlyimpossible with the patient heating devices now in use.

When the antimicrobial mist generator is in-line with a patient warmingdevice circulating heated controlled warm air, the warm air passesthrough the antimicrobial mist generator and becomes substantiallysaturated by evaporated disinfectant forming an aerated mist. As warmair carrying sterilizing mist passes through the non-closed circuitpatient warmer device the disinfectant kills harmful bacteria and germsso that the non-closed circuit patient warmer device's internal chambersare substantially free of bacteria and germs, thereby decreasinginfection risks. Non-closed circuit patient warmer devices include, fornon-limiting example, sterilized blowers with microprocessor-controlledair heating capabilities.

The disinfectant utilized has high volatility so that it is capable ofevaporating and forming a saturated misted airflow upon application ofthe warm air pressure, yet substantially evaporating and dissipating tointernally sterilize the non-closed circuit patient warmer device. Thewarming system circulates all of the warmed air within a closed circuitto provide internal sterilization, so that any air ultimately releasedoutside the non-closed warm air circulating system is sterilized.Preferably, the disinfectant is a volatile liquid component that isadapted to vaporize as forced air blows over said disinfectant. Volatileliquid components preferably include alcohol-based solutions, containingone or more of isopropyl alcohol, ethanol (ethyl alcohol), andn-propanol solutions containing 60% to 95% alcohol. Non-alcohol basedsolutions may contain benzalkonium chloride or triclosan. Alternatively,the disinfectant may be a volatile liquid component saturated within aporous substrate, such as a sponge, capsule, cartridge or filter, andsaid liquid vaporizes and escapes the substrate as forced air blows oversaid substrate. The disinfectant may be in an aqueous solution with analcohol solution or antiseptic therein.

The mist generator may include a transducer facilitating formation ofthe disinfectant mist, such as a piezoelectric transducer deviceincluding a transmitter, receiver, or sensor, for convertinghigh-frequency electronic signals into high-frequency mechanicalvibration. The disinfectant (typically aqueous solution) cavitates intovapor, which is forced through the surface of the disinfectant as a veryfine mist, which is easily absorbed into the airflow. See, for example,http://www.piezo-ultrasonic.com/piezoelectric-transducer-applications-a006.html.

The closed circuit of the warming system is sterilized with anantimicrobial disinfectant spray or atomized mist. The warm aircontained in the closed circulating system is sterile. At the end of useof the bed or blanket, the system can be sterilized with antimicrobialdisinfectant atomized mist if desired and the disposable bed or blanketdiscarded.

The closed-circuit forced hot air warmer consists of a blower connectedby flexible conduit using quick connect or other couplings to a terminaldevice, which may be a blanket or a mattress that is not an open tent.The air that enters the terminal device may pass through a HEPA filterwith a pore size less than 0.22 microns to catch any bacteria orparticles in the incoming airflow. The warm air passes through astructured chamber, or a folded tube within the chamber, so that theblanket or mattress is filled with warm air that passes slowly throughthe device to an outflow port and returns back to the blower in acompletely closed system. There are no apertures to release warm air andno air leaks from the system, avoiding possible turbulence and aircurrents in the operating room. The internal chamber structure ensuresthat warm air is not shunted to the outflow port, but rather fills theentire chamber, so that the entire device remains warm, transmittingheat to the patient by direct contact and maintaining body temperature.The return air conduit is detachable from the device, as well. Theblanket or mattress, therefore, remains a simple, inexpensive device andis suitable for disposal after use.

HEPA filters, if present, at the inflow and outflow portals of theblower, and the fact that each disposable pad is clean, help to avoidbacterial contamination. The unique design of the system makessterilization of the air channels in the blower and the connecting tubeseasy to perform. The detached ends of the flexible inflow and outflowlines are each connected to a small (detachable) chamber. A measuredamount of liquid disinfectant is introduced through a separate port, andthe blower is turned on. The circulating air will take up thedisinfectant, which will be carried through the system as an aerosol.After a brief period, all internal surfaces are disinfected. A secondaliquot of STERILE distilled water can be added later to rinse out thesystem. Following the two steps, a desiccant, paper, or sponge isintroduced, and the blower again turned on. Any residual liquid iscaught in the dry material. The two conduits are then disconnected, thechamber discarded or emptied, and the sterilized system is ready foruse.

A port, which may have a filter, allows ambient air to enter the blowerat the beginning of a cycle. When the system has been filled, and airbegins to return via the outflow conduit, the entry portal closesautomatically or is capped, and only air from the outflow conduit canenter the blower for recirculation.

FIG. 1 illustrates at 100 a system for delivering warm air to patientbeds and blankets in a closed circulating circuit. The closed-circuitwarm air delivery system comprises a blower 101 withmicroprocessor-controlled temperature, pressure, and flow control thathas input and output ports which may be guarded by HEPA filters. Theblower output port is connected to the input port of patient bed orblanket 102 using by flexible tubing with quick release connectors 104.The output port of the patient bed or blanket is connected to the inputport of the blower 101 using flexible tubing again with quick releaseconnectors 104. The microprocessor control panel is shown at 105. Themicroprocessor controls the warm air temperature at 105 a warm airflowrate at 105 b and warm air pressure at 105 c. The warm airflow path is,therefore, a continuous closed circuit with no warm air escape location.The airflow rate is proportional to the speed of rotation of the blowermotor. The electrical current supplied to the heating elements controlsthe warm air temperature.

FIG. 2 illustrates at 200 the blower with air warmer machinery andflexible tubes used being sterilized by the antimicrobial mistgenerator. The blower with air warmer machinery is shown at 101 withHEPA filters both at inlet and outlet. The output of the blower isconnected to the inlet of the antimicrobial mist generator 103 using aflexible hose provided with quick-release couplings. The output of theantimicrobial mist generator 103 is connected to the inlet port of theblower 101 using a flexible hose provided with quick-release couplings.The antimicrobial solution in the antimicrobial mist generator isatomized and circulated in this closed path for a preselected timeperiod, which may be as long as 30 minutes, disinfecting the circuitsterilizing the blower with air warming machinery 101 and all theflexible hoses in the system. At the end of this disinfecting step, thequick release couplings are disconnected and reattached to the blowerand the mat. Any moisture present in the blower 101 and flexible hosescan be blown into a dry sponge.

FIG. 3 illustrates at 300 the details of the microprocessor-controlledblower with warm air delivery 101. As illustrated, the blower has inputport 302, and output port 303 both provided with HEPA filters in theillustration. The quick release connectors of the flexible hose areshown at 104. The warm air flow bath is indicated by the arrows. Theblower with warm air delivery has a blower fan and electrical heatingelements with sensors for air temperature, air pressure, and airflowrate communicating with the microprocessor control as shown in FIG. 1

FIG. 4 illustrates at 400 an embodiment of the antimicrobial mistgenerator, which is only used to achieve internal sterilization of theblower warm air machinery 101 and all the flexible hoses used. The mistgenerator is filled with a capsule 402 that has the antimicrobial liquidsealed with gasket 403, which is atomized by the flow of warm airthrough the input port and is delivered to the output port. In analternative embodiment, a microprocessor may be provided, whichpreferably turns on the antimicrobial mist spray during initial set upto sterilize the interior surfaces of the blower and flexible tubes.When the sterilization operation is complete, an aliquot of steriledistilled water is introduced, and any residual disinfectant isvaporized in the circulated water vapor. Any remaining water can betaken up into a clean sponge or desiccant. Quick-release couplings 104connect the flexible hoses to the inlet and outlet of antimicrobial mistgenerator 103. The mist generator is then disconnected from bothflexible hoses and discarded.

FIG. 5 illustrates at 500 the patient bed or blanket 102 for a closedsystem. The inlet of warm air into the bed or blanket is shown at 501.The patient bed or blanket has a plurality of interconnected airflowpaths indicated by arrows shown at 503. The outlet of the patient bed orblanket 102 is shown at 502. The connection of a flexible hose to theinlet and outlet is made using quick-release couplings 104.

FIG. 6 illustrates at 600 an optional arrangement for the sterilizationprocess of the patient bed or blanket. This is similar to FIG. 1 exceptthat the antimicrobial mist generator 103 is inserted between the blowerwarm air machinery 101 and the patient bed or blanket 102, and a closedcircuit is formed using flexible hoses with quick release connectors104. When used prior to disposal, the sterilization process can be runfor about 15 minutes, and the sterilized patient bed or blanket is thendiscarded.

FIG. 7 illustrates another embodiment of the microprocessor-controlledantimicrobial mist generator, shown generally at 700. FIG. 8 illustratesthe embodiment of FIG. 7 in-line with a non-closed circuit blower, showngenerally at 800, forming a temporarily closed circuit.

Referring to FIGS. 7 and 8, the antimicrobial mist generator 703 is onlyused to achieve internal sterilization of the blower warm air machineryand all the flexible hoses associated therewith. The mist generatorcomprises a main body 701 having a top wall 730 with an opening 730′with a removable cap, the opening traversing into a chamber 702 adaptedto receive a disinfectant shown generally at 702′ (misting shown in FIG.8 at 702″), side walls 703 and a bottom wall 704 that may include abottom cover to allow access into the chamber of the main body forinserting and later removing desiccant and the like. The main body 701further includes an inlet duct 705 adapted for attachment to a firsthose 706 which, in turn, is adapted for attachment to an output opening711 of a blower 710 for delivery of forced air into the chamber 702 tocarry disinfectant misted air. The main body 701 also includes an outputduct 707 adapted for attachment to a second hose 708 which in turn isadapted for attachment to a blower inlet 712 opening of the blower 710for delivery of disinfectant misted air through internal components ofthe blower 710 to improve sterility of the blower 710 to mitigatemicrobial contamination of patient warmers and lifters and hospitalenvironments when the blower is in use. Second hose 708 is attached tothe blower inlet 712 by way of an attachment or modification to theinflow of the blower to accept that hose, shown generally at 708′. Theblower with air warmer machinery is shown at 710 with HEPA filters ateach inlet 712 and outlet 711.

The top wall opening 730′ preferably includes a narrow (˜5 cm) neckclosed with a removable cap so that disinfectant, water, dry desiccant,etc., can be introduced through the neck/opening 730′. Owing to thenarrow neck and opening 730′, desiccant and other bulky solids cannot beeasily removed, and therefore re-use is avoided. However, if the mistgenerator is not disposable, the bottom wall may include a bottomcap/base that is removable by screwing the same off to permit emptyingof the mist generator.

Capsule or chamber 702 has the antimicrobial or disinfectant liquidsealed with a gasket/diaphragm, preferably at opening 730′. The liquidis atomized by the flow of warm air through the input port and isdelivered to the output port. In an alternative embodiment, a transducerfor misting the liquid may be provided. The antimicrobial mist generatormay be microprocessor controlled wherein the controls turn on anantimicrobial mist spray during initial set up to sterilize the interiorsurfaces of blower air machinery and flexible tubes attached thereto.When the sterilization operation is complete, an aliquot of steriledistilled water is introduced, and any residual disinfectant isvaporized in the circulated water vapor. Any remaining water can betaken up into a clean sponge or desiccant. Quick-release couplings 104connect the flexible hoses to the inlet and outlet of antimicrobial mistgenerator 103. The mist generator is then disconnected from bothflexible hoses and discarded.

The antimicrobial mist generator is capable of being utilized as astand-alone internal sterilizer for non-closed-circuit patient warmers.Antimicrobial mist generator includes a mist chamber for housing adisinfectant adapted to vaporize or form a mist upon contact with warmair. Preferably the outflow/outlet of the chamber is attached toflexible hose 704 connected to any non-closed circuit device,temporarily making it run as a closed circuit and allowing internalsterilization, including drying, without releasing the disinfectantvapor into the hospital environment. The generator, presumably, but notnecessarily disposable, would achieve the internal sterilization that iscurrently impossible with the blower devices now in use.

Flexible hoses (fixed or detached) are attached to the mist generatorvia the inflow part of a warmer that is not closed circuit, creating atemporary closed circuit that allows internal sterilization. An aliquotof sterile water can be introduced after the sterilization takes placeto remove residual disinfectant. A sponge or descant is inserted, andthe system is again run to remove residual liquid/vapor.

FDA required “regular cleaning” of patient heating devices can beachieved with the subject system without changing any other components.Heated air takes up the fluid within the chamber whereupon it continuestraveling with the warm forced air as a mist or vapor through tubes tosterilize devices attached thereto. Fluids contemplated include chemicalcompositions having relatively low boiling points or volatility so thatthe disinfectant vaporizes upon being heated by way of the warm air.Examples include alcohols such as ethanol etc.

FIG. 9a illustrates another embodiment of the antimicrobial mistgenerator, shown generally at 900. The antimicrobial mist generator 903is generally used to achieve internal sterilization of the blower warmair machinery and all the flexible hoses used. The mist generator isfilled with a capsule 902 that has the antimicrobial liquid sealed withgasket/diaphragm 905, which is atomized by the flow of warm air throughthe input port and is delivered to the output port. The antimicrobialmist generator 903 turns on the antimicrobial mist spray during initialset up to sterilize the interior surfaces of blower air machinery andflexible tubes attached thereto. When the sterilization operation iscomplete, an aliquot of sterile distilled water may be introduced, andany residual disinfectant is removed in the circulated water vapor.Quick-release couplings 904 connect the flexible hose to the inlet ofantimicrobial mist generator 903. Antimicrobial mist generator 903preferably includes an outlet 903′ whereupon either a cap 906 or a quickrelease coupling 904 connecting to a flexible hose is preferablyprovided for connection of the mist generator 903 to patient warmerdevices including for example blower warm air machinery (see FIGS. 2 and10), or a mattress or a bed for sterilization thereof (see FIG. 6). Themist generator is disconnected from both flexible hoses after the systemis dried internally by running the blower, and excess water is taken upinto a clean sponge or desiccant.

The antimicrobial mist generator 903 is capable of being utilized as astand-alone internal sterilizer for non-closed-circuit patient warmers(such as without limitation the kind use by 3M associated with the tradename BAIR and others). Antimicrobial mist generator 903 includes a mistchamber 910 for housing a disinfectant adapted to vaporize or form amist upon contact with warm air. In this use, the outflow/outlet 903′ ofthe chamber 910 is attached to flexible hose 904 connected to anon-closed circuit device, temporarily making it run as a closed circuitand allowing internal sterilization, including drying, without releasingthe disinfectant vapor into the hospital environment (See FIG. 10). Thegenerator, presumably, but not necessarily disposable, would achieve theinternal sterilization that is currently impossible with the patientheating devices now in use. Preferably the mist generator 903 is shapedhaving a neck portion 921 at the top with a diameter substantially lessthan the diameter of a bottom portion 922. Preferably, neck portion 921has a diameter of approximately 5 cm, which is substantially less thanthe diameter of a bottom portion 922 which, in turn, preferably includescurved walls so that the bottom portion is substantially bulbous. Thebottom portion 922 may include a bottom opening with a removable bottomcover 923 that affords access to the chamber of the mist generator toallow addition and later removal of desiccant or fibers that can absorbcirculating moisture, the cover 923 being necessary only if the mistgenerator is designed and employed for multiple use. The preferredembodiment is for the bottom portion to be solid, making it difficult toremove the solid desiccant that was easily introduced through the narrowneck of the upper portion 921, encouraging single-use and disposal ofthe used mist generator, thus avoiding the release of contaminatedmaterial and disinfectant into the hospital environment

Flexible hoses (fixed or detached) from the outlet flow port of the mistgenerator to the inflow port of a blower that is a non-closed circuit,creating a temporary closed circuit that allows internal sterilization.An aliquot of sterile water can be introduced after the sterilizationtakes place to remove residual disinfectant, and then removed by uptakeinto a sponge or descant.

FDA recommended, “regular cleaning” of patient heating devices can beachieved with the subject system without changing any other components.Preferably to avoid a port into the chamber 910 that could be opened forfilling, a soft diaphragm 905 is provided through which fluids can beintroduced with a needle and syringe (similar to medicine vials). Thedisinfecting liquid may be contained in a sealed prefilled capsule,which is perforated when pushed into the chamber 910, releasing theenclosed fluid. The heated air causes the fluid of capsule 902 toatomize within chamber 910, whereupon it continues traveling with thewarm forced air as a mist or vapor through tubes to sterilize devicesattached thereto. Fluids contemplated include chemical compositionshaving relatively low boiling points or volatility so that thedisinfectant vaporizes upon being heated by way of the warm air.Examples include alcohols such as ethanol etc. Embodiments of thecapsule/cartridge are shown in FIGS. 9b -9 d.

FIG. 9b illustrates another embodiment of a capsule/cartridge 950adapted to be inserted within the mist generator of FIG. 9a .Capsule/cartridge 950 is a spray cartridge containing a liquiddisinfectant/antimicrobial solution generally constructed as a spraybottle construction, including a reservoir 951 housing the liquid havinga tube 952 therein. A cartridge pump 953 is provided with a triggermechanism, a piston, a cylinder, and a one-way valve in-line with aspray nozzle 954. Spray nozzle 954 includes a one-way valve to preventair from flowing back into the pump and allowing suction within the pumpso that liquid is pulled through tube 952. Nozzle 954 concentrates theliquid into a stream forcing it through a small hole. When the triggeris pressed, it forces the piston into the cylinder, which forces theliquid through the nozzle as a concentrated stream of liquid. When thetrigger is released, the piston moves back, pulling liquid back into thecylinder. This liquid is forced out of the nozzle the next time thetrigger is pressed. A one-way valve at the bottom of the pump onlyallows liquid to flow up the tube into the pump, not back into thebottle. The mist generator preferably includes a spray activator hereinshown as a bracket 955 that the capsule/cartridge 950 sits within whenit is inserted in the chamber of the mist generator. Bracket 955 may beprovided so that it is in-line with a manual button that, whendepressed, presses the capsule/cartridge 950 downward and causes thetrigger of the pump to be activated to release spray. Preferably,bracket 955 is in-line with an electronic switch that activates thetrigger to cause release of the spray.

FIG. 9c illustrates an embodiment of a capsule/cartridge 960 adapted tobe inserted within the mist generator of FIG. 9a . In this embodiment,capsule/cartridge 960 includes a reservoir 961 holding a volatiledisinfectant liquid and side walls 962 having at least a portion thereinthat include small apertures or perforations 963 for release of mistedliquid as air passes through the chamber of the mist generator. It isnoted that the reservoir 961 may hold a volatile disinfectant liquid, ora semi-solid or membrane holding the liquid that releases the liquid asforced heated air passes through the chamber of the mist generator.

A separate capsule/cartridge may be provided housing a fiber ordesiccant when the mist generator is in a drying mode, such as after thedisinfectant procedure is complete. The user simply places acapsule/cartridge housing the disinfectant into the chamber of the mistgenerator and runs a disinfectant operation for a period of time asshown in FIG. 10. When the disinfectant run is complete, the user cansimply remove the capsule/cartridge and replace it with a dryingcapsule/cartridge that contains fiber or desiccant and performs a dryingrun for a period of time to dry liquid/residual mist from the generator,tubes, and blower. Upon completion, the capsules/cartridges, as well asthe mist generator itself, are preferably discarded.

FIG. 9d illustrates another embodiment of a capsule/cartridge 970adapted to be inserted within the mist generator of FIG. 9a . In thisembodiment, the reservoir 971 housing the disinfectant is located withina capsule chamber 972. At least a portion of side walls 973 of thereservoir has apertures or holes therein for the escape of misteddisinfectant as air passes through the chamber of the mist generator.

FIG. 10 illustrates at 1000 another embodiment of the blower with airwarmer machinery and flexible tubes being sterilized by theantimicrobial mist generator. The blower with air warmer machinery isshown at 1001 with HEPA filters both at inlet and outlet 1001′ and1001″. The output 1001″ of the blower 1001 is connected to the inlet ofthe antimicrobial mist generator 1003 using a flexible hose providedwith quick-release couplings. The output of the antimicrobial mistgenerator 1003 is connected to the inlet port 1001′ of the blower 1001using a flexible hose provided with quick release couplings temporarilyforming a closed-circuit system. The antimicrobial solution in theantimicrobial mist generator is atomized and circulated in this closedpath for a preselected time period, which may be as long as 15 minutes,disinfecting the circuit sterilizing the blower with air warmingmachinery 1001 and all the flexible hoses in the system. At the end ofthis disinfecting step, any moisture present in the blower 1001 andflexible hoses is taken up into a dry sponge. The quick-releasecouplings are then disconnected.

The microprocessor control panel is shown at 1005. The microprocessorcontrols the warm air temperature at 1005 a warm airflow rate at 1005 band warm air pressure at 1005 c. The warm airflow path is, therefore, acontinuous closed circuit with no warm air escape location. The airflowrate is proportional to the speed of rotation of the blower motor. Theelectrical current supplied to the heating elements controls the warmair temperature.

FIG. 11 illustrates another embodiment of the subject mist generator,shown generally at 1100. The mist generator comprises a main body 1101having a top wall 1111 with an opening 1111′, the opening traversinginto a chamber 1102 adapted to receive a disinfectant shown generally at1102′, side walls 1103 and a bottom wall 1104. The main body 1101further includes an inlet duct 1105 adapted for attachment to a firsthose which in turn is adapted for attachment to an output opening of ablower for delivery of forced air into the chamber 1102 to create misteddisinfectant in the air. The main body 1101 also includes an output duct1107 adapted for attachment to a second hose, which in turn is adaptedfor attachment to a blower inlet opening of the blower for delivery ofdisinfectant misted air through internal components of the blower. Inthe embodiment shown, the bottom wall 1104 includes a bottom openingwith a removable bottom cover 1131, which can cause the removal of themain body 1101 from bottom cover 1131 for insertion of desiccant, and/orpaper towels, etc. In the embodiment shown, cover 1131 also includes anoptional transducer 1150 for vibration misting the liquid within thechamber.

FIGS. 12a-12b illustrate an embodiment of the antimicrobial mistgenerator for temporarily creating a closed circuit to sterilizeinternal structures with disinfectant vapor for a convective temperaturemanagement system used in a hospital or surgery center. FIG. 12aillustrates the antimicrobial mist generator appointed for attachment tothe temperature management system, shown generally at 1200. FIG. 12billustrates the antimicrobial mist generator temporarily attached to theantimicrobial mist generator for sanitization. The convectivetemperature management system is appointed to be used in a hospital orsurgery center to maintain a patient's core body temperature, such asthat referred to as the Bair Hugger by 3M.

The system generally consists of a reusable warming unit or blower 1201and a single-use disposable warming blankets for use before, during, andafter surgery. A mist generator for improved sterility of blowers havingcontrolled forced air delivery is shown at 1220 having a top wall withan opening having a cap 1221′ that traverses into a chamber 1221.Chamber 1221 is adapted to receive a liquid disinfectant/antibacterialsolution and/or water shown generally at 1222 inserted into chamber1221. Alternatively, disinfectant/antibacterial solution and/or water isabsorbed in a sponge or porous surface wherein thedisinfectant/antibacterial solution and/or water is absorbed that isappointed to be placed within chamber 1221. An inlet duct 1223 isintegrated in chamber 1221, which is adapted for attachment to a firsthose 1224 which, in turn, is adapted for attachment to an output opening1225 of the blower 1201 for delivery of forced air into the chamber 1221to carry disinfectant misted air. Chamber 1221 includes an output duct1226 adapted for attachment to a second hose 1227 which, in turn, isadapted for attachment to a blower inlet opening 1201′ of the blower1201 for delivery of disinfectant misted air through internal componentsof the blower 1201 so that the mist generator improves sterility of theblower 1201 to mitigate microbial contamination of patient warmers andlifters and hospital environments. A closed-circuit is temporarilycreated to sterilize the internal structures of the otherwise opencircuit heating device of the blower 1201 with disinfectant vapor.

Second hose 1227 includes an attachment end 1228 formed to substantiallycompletely cover and substantially seal over the blower inlet opening1201′ of blower 1201. Preferably, attachment end 1228 is constructedhaving a substantially flat rim 1229 with an adhesive surface 1230 foradhering attachment end 1228 against blower 1201 sealing around blowerinlet opening 1201′. A seal or gasket may be integratedcircumferentially around the entire rim 1229 for forming a substantiallywater-tight seal. After sterilization is complete and the liquid dry, adry desiccant 1240 is appointed to be inserted into the chamber 1221 todry the internal components of the blower 1201, hoses, and mister.

FIG. 13 illustrates an embodiment of an antimicrobial mist generator1320 temporarily attached to a blower 1301 of a hospital ventilator,anesthesia machine, or oxygen support system. Mist generator 1320 has atop wall with an opening with lid/cap 1321′ that traverses into achamber 1321 that receives a disinfectant/antibacterial solution and/orwater shown generally at 1322. Chamber 1321 has an inlet duct 1323attached to a first hose 1324 attached to an output opening 1325 of theblower 1301 for delivery of forced air into the chamber 1321 to carrydisinfectant misted air. Chamber 1321 includes an output duct 1326adapted for attachment to a second hose 1327 which, in turn, is adaptedfor attachment to a blower inlet opening of the blower 1301. Second hose1327 includes an attachment end formed to substantially completely coverand substantially seal over the blower inlet opening of blower 1301.After sterilization is complete and the liquid dry, a dry desiccant isappointed to be inserted into the chamber 1321 to dry the internalcomponents of the blower 1301, hoses, and mister. The chamber, liquidand/or desiccant can all be single-use and/or disposable.

FIG. 14a illustrates another embodiment of the antimicrobial mistgenerator in which a closed circuit is temporarily created to sterilizeinternal structures with the disinfectant vapor of a heating/cooling/aircirculation device. FIG. 14b illustrates a top plan view wherein thedisposable filter/sponge, which becomes a sterilizing grid, is insertedinto the slot normally occupied by the dry dust filter and the system istemporarily configured into a closed circulating circuit forsterilization. Disposable filter/sponge 1420 is sized and shaped to fitinto the system's filter slot or filter port 1402.

System 1401 includes a chamber 1400 removably connected to an airhandler 1404 connected to a main vent 1405, in turn, feeding to vents1406 a, 1406 b, and 1406 c. All but one outlet/vent is closed, hereinvents 1406 b and 1406 c are closed, and vent 1406 a remains open and isconnected by a hose 1424 with an attachment end 1428 formed tosubstantially completely cover and substantially seal over a return duct1423 of chamber 1400 of system 1401 (see FIG. 14b ). When the hose 1424attachment end 1428 is placed over return duct 1423 and the disposablefilter/sponge inserted in to the filter slot of chamber 1400 the closedsystem is then run.

Disinfectant filter/sponge 1420 is formed as a sterilizing grid with ascreen or pores more open than a standard filter coated with a softporous surface material that holds liquid disinfectant or water.Alternatively, filter/sponge may be dry and/or impregnated prior toinsertion. Air flowing through will take up and distribute disinfectantto internal surfaces of the system and sterilize them. Aftergrid/disinfectant filter/sponge 1420 is dry, it is removed, and the samefilter/sponge or grid is impregnated, or another is inserted, and wateris taken up by flowing air and distributed throughout the system.Additional water may be added, and disinfectant is taken up in thewater. The grid/filter/sponge 1420 is removed and another grid,composed, covered or filled with a desiccant material is inserted. Asmoving air carries internal moisture to the desiccant here, it isabsorbed. The grid/filter/sponge 1420 is then removed and discarded andthe standard dust filter reinserted in the system. The internal portionof the system is now sterilized, and the circulating air is free of anydisinfectant.

To establish a closed system, vents 1406 a and 1406 b must be coveredand closed during operation. The circulating air returns to the systemvia a return vent 1423. Any additional return vents must be occluded,either by an adhesive plastic wrap (i.e., such as that sold under thename saran wrap) or by some other cover or wrap 1428, which may haveadhesive edges for fixation. Airflow within the system requires anoutlet to be left open, and a conduit 1420 from the open outlet to thereturn vent 1423 or central return duct 1400 The conduit may bedisposable, attaching temporarily at both the outlets and over thereturn, or installed permanently, in which case an internal shut offwithin the conduit 1424 may be required.

Having thus described the invention in rather full detail, it will beunderstood that such detail need not be strictly adhered to, but thatadditional changes and modifications may suggest themselves to oneskilled in the art, all falling within the scope of the invention asdefined by the subjoined claims.

What is claimed is: 1) A mist generator for improved sterility ofblowers having controlled forced air delivery, comprising: a) a mainbody having a top wall with an opening, the opening traversing into achamber adapted to receive a disinfectant, side walls, and a bottomwall; b) an inlet duct or aperture adapted for attachment to a firsthose which in turn is adapted for attachment to an output opening of theblower for delivery of forced air into the chamber to carry disinfectantmisted air; c) an output duct or aperture adapted for attachment to asecond hose which in turn is adapted for attachment to a blower inletopening of the blower for delivery of disinfectant misted air throughinternal components of the blower; whereby the mist generator improvessterility of the blower to mitigate microbial contamination of forcedair delivery systems. 2) The mist generator as recited by claim 1,wherein said blower is part of a closed circuit. 3) The mist generatoras recited by claim 1, wherein said blower having controlled forced airdelivery is a commercial or residential heating or cooling system. 4)The mist generator as recited by claim 1, wherein said blower havingcontrolled forced air delivery is a ventilator or respirator. 5) Themist generator as recited by claim 1, wherein said blower havingcontrolled forced air delivery is an anesthesia device. 6) The mistgenerator as recited by claim 1, wherein said blower hasmicroprocessor-controlled air heating capability for delivery of heatedforced air, and said disinfectant is adapted to evaporate due to theheated forced air to yield misted air containing disinfectant. 7) Themist generator as recited by claim 6, wherein said disinfectant is avolatile liquid component that is adapted to vaporize as forced airblows over said disinfectant. 8) The mist generator as recited by claim6, wherein said disinfectant is a volatile liquid component saturatedwithin a substrate and said liquid vaporizes and escapes said substrateas forced air blows over said substrate. 9) The mist generator asrecited by claim 1, wherein said mist generator is disposable. 10) Themist generator, as recited by claim 1, wherein said disinfectant iscontained in a capsule adapted to be inserted within said chamber ofsaid mist generator. 11) A mist generator for improved sterility ofblowers having controlled forced air delivery, comprising a disinfectantfilter formed as a sterilizing grid having a screen coated with a softporous surface material impregnated with a liquid disinfectant, whereinsaid soft porous surface material releases or dissolves to release saidliquid disinfectant, whereby the mist generator improves sterility ofthe blower to mitigate microbial contamination of forced air deliverysystems. 12) The mist generator as recited by claim 11, wherein saidsoft porous material is a starch material that dissolves to release thedisinfectant liquid located therein. 13) The mist generator as recitedby claim 11, wherein said soft porous material is a gelatin materialthat dissolves to release the disinfectant liquid located therein. 14)The mist generator as recited by claim 11, wherein said blower is partof a closed circuit. 15) The mist generator as recited by claim 11,wherein said blower having controlled forced air delivery is acommercial or residential heating or cooling system and wherein saiddisinfectant filter is adapted to be temporarily fitted in saidcommercial or residential heating or cooling system.